The present invention relates to a counterweight removal device for construction equipments such as cranes and hydraulic excavators. Regarding a counterweight for this type of conventional construction machine, it is common for the swing frame to be provided with horizontal weight bearing extensions on its rear end, on which the counterweight is placed so as to be screwed on said frame. However, said counterweight has to be lifted so as to clear the weight bearing extensions and moved forward so as to lean against the mounting frame and fixed with set screws, because the weight bearing extensions themselves stand on the uplifting route of the counterweight.
It is therefore, necessary to have some means for lifting or lowering the counterweight vertically and for moving it forward or backward. The crane or the like requires other auxiliary heavy equipment for handling proper counterweight in the field, or some proper heavy device of complicated structure just to mount and dismount the counterweight.
Shown in the FIG. 8 is a counterweight handling system, disclosed by the Japanese Patent Application Laid-open No. 59-1625, wherein a lift cylinder for operating an arm pivoted on the rear end of a swing frame of said equipment is mounted for replacing said counterweight and bearing an extension, by which the counterweight is lifted so as to be fixed on the swing frame with shear pins and set screws.
However, it is necessary to provide an arm pivoted on the frame and a lift cylinder on the counterweight lifting system as aforementioned. The counterweight mounting operation is not easy because of hard positioning of shear pins for bearing a counterweight. Further, this type of counterweight lifting system is rather expensive.